Fluoroscopic Confirmation of Needle Location in Ultrasound-guided Genicular Nerve Radiofrequency Thermocoagulation.

BACKGROUND: Radiofrequency thermocoagulation of genicular nerves is an effective treatment for chronic pain due to knee osteoarthritis. The procedure can be performed under fluoroscopic or ultrasonographic guidance. OBJECTIVES: The aim of this study was to fluoroscopically check the final location  of the needle in ultrasound-guided genicular nerve radiofrequency thermocoagulation and evaluate the treatment's success in patients with knee pain. STUDY DESIGN: A 2-center, prospective study. SETTING: A private clinic and a tertiary care health center. METHODS: Thirty-two patients who had unilateral knee pain, and grade 3-4 knee osteoarthritis according to the Kellgren-Lawrence classification were included. Following diagnostic genicular nerve blocks in patients whose knee pain was relieved by >= 50%, radiofrequency thermocoagulation was applied to these nerves. The final position of the needle was checked via fluoroscopy in anteroposterior and lateral planes. RESULTS: The needle was located in the one-third anterior portion of the bone shaft in 69 of 96 patients (71.9%), between one-third and two-thirds in 21 (21.9%), and in the one-third posterior portion in 6 (6.3%). The mean Numeric Rating Scale score for pain was 7.69 ± 0.99 before treatment, 4.03 ± 1.26 at one week, 2.53 ± 1.24 at one month, and 2.19 ± 1.71 at 3 months, indicating a statistically significant decrease (P < 0.001). LIMITATIONS: The lack of a study group in which genicular nerve radiofrequency thermocoagulation was performed under fluoroscopy guidance could be cited among the limitations of this clinical study. CONCLUSIONS: The final position of the needle tip in radiofrequency thermocoagulation of genicular nerves can exist at the one-third anterior of the bone shaft, without a need for further advancing the needle to the posterior portion. Although performed more distally compared to fluoroscopy guidance, ultrasound-guided genicular nerve radiofrequency thermocoagulation still provides effective analgesia.

Plasma Levels of Kynurenine, Soluble OX40 and Mir-138-5p Are Associated With Tumor-infiltrating Lymphocytes in Colorectal Cancer: An Exploratory Study.

BACKGROUND/AIM: Colorectal cancer (CRC) is one of leading cancers in terms of incidence and mortality. Interaction of tumor cells with the surrounding microenvironment plays a crucial role in the development and progression of CRC. Many pathways such as the kynurenine pathway, OX40/OX40L-mediated signaling and microRNAs targeting PD-L1 may be involved in CRC development by affecting T cell activation, thus creating an immune-deficient microenvironment. Herein, our goal was to assess the association between plasma levels of tryptophan (TRP), kynurenine (KYN), KYN/TRP ratio, soluble OX40 (sOX40) and PD-L1-targeting miR-138-5p and CRC risk. PATIENTS AND METHODS: Plasma concentrations of TRP and KYN were determined by HPLC; sOX40 was measured by ELISA whereas circulating miR-138-5p was measured by quantitative PCR in pathologically confirmed CRC patients and colonoscopy-verified CRC-free controls without polyps (control group 1) and with polyps (control group 2). RESULTS: We found significantly lower plasma levels of TRP in CRC patients compared to control groups which resulted in significantly higher KYN/TRP ratio in CRC patients than in the controls (p=0.007). Plasma levels of sOX40 did not significantly differ between groups. The levels of circulating miR-138-5p were significantly lower in CRC patients (relative median value 0.02) than in the control groups (relative median values 0.2 and 4.29, respectively) (p=0.03). Plasma levels of KYN and sOX40 were considerably higher in patients with no tumor-infiltrating lymphocytes (TILs) than those with TILs whereas circulating miR-138-5p had opposite expression pattern in plasma. CONCLUSION: The kynurenine pathway and miR-138-5p are associated with CRC risk and plasma levels of KYN, sOX40 and miR-138-5p are related to TILs, making them possible target molecules in possible immunotherapeutic targets for CRC.

Androgen Receptor Blockade Using Enzalutamide Suppresses Long Non-Coding RNA ARLNC1 in Prostate Cancer Cells.

Prostate cancer (PCa) is a common malignant disease with high mortality rates that develops and progresses in an androgen-dependent way. In recent years, RNA sequencing enabled identification of many PCa-related long noncoding RNAs including androgen receptor-regulated long non-coding RNA 1 (ARLNC1) and prostate cancer-associated transcript 1 (PCAT1). In the present study, our goal was to illuminate expression changes of ARLNC1 and PCAT1 in the context of androgen stimulation or androgen receptor (AR) blockade with respect to AR expression status. In this experimental study, LNCaP cells and higher AR-expressing LNCaP-AR++ cells were used as cell models. Cells were treated with dihydrotestosterone (DHT) as an androgen stimulator and/or enzalutamide as an AR inhibitor. Cell viability was assessed using annexin V and propidium iodide (PI) staining in flow cytometry. Androgen stimulation prompted baseline ARLNC1 levels by 53.5-fold in the LNCaP cells (P=0.01) and by 25-fold in the LNCAP-AR+ cells (P=0.18). AR inhibition by enzalutamide reduced baseline ARLNC1 in LNCaP-AR++ cells by 2-fold (P=0.01), but to a lesser extent in LNCaP cells. Co-treatment of cells with DHT and enzalutamide led to a remarkable decrease in the DHT effect on ARLNC1 expression. No specific effect of androgen stimulation or AR blockade on PCAT1 expression was detected. Our results revealed that the extent of induction of ARLNC1 by androgen is modulated by receptor expression status. In addition, we determined that AR blockade, via enzalutamide, effectively suppresses ARLNC1 both at baseline and after induction by DHT.

Easy to treat when the diagnosis is made: Three cases of clunealgia and the advantage of ultrasonography.

In this article, we present three cases of clunealgia admitted with low back pain. Their pain relieved with superior cluneal nerve block. The posterior side of the iliac crest, which is the location where the superior cluneal nerve passes, was identified using a high-frequency linear transducer. The drug injected separates the erector spinae muscle and thoracolumbar fascia and accumulates between these two structures. All patients were discharged with a complete pain relief. This report highlights the fact that superior cluneal nerve entrapment should be kept in mind in patients with low back pain and that ultrasound guidance can correctly identify the infiltration and eliminate anesthetization of other surrounding structures.

Ultrasound-Guided Erector Spinae Plane Block and Trapezius Muscle Injection for Myofascial Pain Syndrome.

OBJECTIVE: There were two goals to this study: the first goal was to research the analgesic effectiveness of erector spinae plane block (ESPB) added to the treatment after trapezius muscle injection (TMI) and the second was to investigate whether repeated TMI increases the analgesic effect in myofascial pain syndrome (MPS). METHODS: Sixty patients with a diagnosis of MPS were randomized into two groups. The TMI group (n = 30) received ultrasound-guided (USG) TMI with 5 mL of 0.25% bupivacaine two times, with a 1-week interval in between. The ESPB group (n = 30) received USG TMI with 5 mL of 0.25% bupivacaine in the first week and USG ESPB with 20 mL of 0.125% bupivacaine in the second week. The pain severity of the patients was evaluated using the visual analog scale (VAS). The data obtained before (week 0) and after (weeks 1, 2, 3, and 4) the injections were statistically compared between the groups. RESULTS: In both groups, the mean VAS score decreased in the first week compared to the mean pretreatment score (p < .001). When the VAS scores were compared between the first and second weeks, a decrease was observed in both groups (p < .001), but it was more evident in the ESPB group. Compared to previous weeks, there was no significant difference in VAS scores at the third and fourth weeks. CONCLUSIONS: The analgesic effect of repeated TMI for MPS was superior to a single injection, but ESPB combined with TMI provided more effective analgesia than repeated TMI.

Fragmentation Analysis of Plasma DNA Reveals Its Prognostic Value in Gastric Cancer.

BACKGROUND: Gastric cancer (GC) is a common cause of cancer-related deaths. The poor clinical outcome in GC patients is partially associated with a lack of appropriate diagnostic and prognostic biomarkers. In the present study, we evaluated the diagnostic and prognostic values of cell-free DNA (cfDNA) integrity and the concentration of circulating nucleosomes (cNUCs). METHODS: In the study, 40 GC patients and 55 GC-free individuals were enrolled. Cell-free DNA integrity was calculated as the ratio of concentration of the longer ACTB (beta-actin) gene fragment to that of the shorter ACTB fragment, measured using quantitative PCR. Circulating nucleosomes were measured by an ELISA-based approach. RESULTS: We found that cfDNA integrity is higher in GC patients than in the control subjects (relative median values 0.51 vs. 0.38, respectively, P = .56) indicating prominent abundance of longer fragments in the patients. The patients with larger tumors (T3-4) had significantly higher cfDNA integrity than those with T1-T2 tumors. We also found GC patients to have higher concentrations of cNUCs in their plasma (relative median values 3.64 vs. 3.1). Importantly, the patients with high cfDNA integrity (i.e., lower fragmentation) had longer overall survival rates at 3 years than those with lower cfDNA integrity (76.5% vs. 38.9%, P = .02). CONCLUSION: Cell-free DNA fragmentation has a prognostic value. However, it has no diagnostic value in GC.

Satellite 2 repeat DNA in blood plasma as a candidate biomarker for the detection of cancer.

BACKGROUND AND AIM: Currently, cancer biomarkers are associated with low diagnostic performance, and the notion of using cell-free DNA (cfDNA) as a surrogate cancer biomarker is a subject of ongoing research efforts. Pericentromeric satellite repeats were shown to expand in tumor cells. Here, we hypothesized that the increased release of satellite DNA into the circulation might be a basis for developing a biomarker for the detection of cancer. MATERIALS AND METHODS: The study included patients with different cancer types, and controls without cancer. Human satellite 2 repeat (HSATII) from chromosomes 1, 10, or 16 was amplified using extracted DNA from plasma or direct application of diluted plasma in PCR. RESULTS: We first showed that HSATII DNA levels were higher in patients with cancer than in controls relative to LINE1 element, with chr10-HSATII being the most relevant. Absolute quantification in digital PCR showed much higher levels of chr10-HSATII in patients with breast cancer compared with healthy individuals. Subsequently, employing diluted plasma also revealed that HSATII DNA was present in increased levels in patients with cancer including breast, gastric, lung or bile cancers, sarcoma or Hodgkin's lymphoma than in controls with an AUC of 94% in the ROC curve. CONCLUSIONS: This proof-of-concept study reveals the high potential of HSATII DNA as a surrogate cancer biomarker.

Impact of histone methyltransferase SUV420H2 in breast cancer.

Breast cancer is the most common type of cancer in women worldwide. Triple methylation of H4 lysine 20 (H4K20me3), a key component of epigenetic regulation of genomic integrity, is catalyzed by the methyltransferase, SUV420H2. Data on the expression status of SUV420H2 in breast cancer are limited. In the present study, the influence of SUV420H2 suppression on the proliferation of breast cancer cells was experimentally investigated. Subsequently, SUV420H2 expression was assessed in resectable breast cancer along with H4K20me3 status. SUV420H2 expression was knocked down in breast cells using small interfering RNA oligonucleotides. SUV420H2 expression was determined semi-quantitatively at the mRNA level. H4K20me3 was measured on extracted histone proteins using an approach similar to ELISA. Suppression of the SUV420H2 gene resulted in increased cell proliferation. Although the median SUV420H2 expression values were similar in tumor tissues and non-cancerous regions in the entire cohort (0.0022 and 0.0015, respectively; P=0.46), there was a notable difference in expression between tumor tissues and the adjacent non-cancerous region in the majority of patients. Increased SUV420H2 expression in tumors compared with healthy tissue was predominantly observed in patients with early-stage breast cancer, whereas reduced SUV420H2 expression was observed in tumors more frequently in patients with advanced stage diseases. There was no association between SUV420H2 expression and the tissue levels of H4K20me3. The results showed that SUV420H2 exhibited anti-proliferative activity in vitro, and exhibits a heterogeneous expression pattern in breast cancer tissues.

Circulating lncRNA H19 may be a useful marker of response to neoadjuvant chemotherapy in breast cancer.

BACKGROUND: Novel biomarkers are needed to predict the effectiveness of the treatment of presurgical neoadjuvant chemotherapy (NAC) in breast cancer (BC). OBJECTIVE: This is an exploratory study to assess the impact of 3 cancer-related long non-coding RNAs (lncRNAs) (H19, MALAT1 and GA5) in blood plasma of patients with BC in predicting the response to NAC. METHODS: The plasma levels of RNAs were relatively measured by quantitative PCR at baseline, and at the end of the fourth cycle of NAC in patients with locally advanced BC. RESULTS: Only H19 was associated with patients' characteristics, and with the response to NAC. Higher plasma expression of H19 was associated with younger age at diagnosis, triple negative tumors, and Ki-67 index. Patients with a pathological complete response (20%) had lower pre-therapeutic levels of H19 compared with the non-complete responders (relative levels 0.1 vs 0.2, respectively, P: 0.04). In addition, the patients with higher degree of downstaging of initial tumors had lower baseline levels of H19 among non-complete responders. CONCLUSION: Our study reveals that H19, but not MALAT1 and GAS5, may be a useful marker of response to NAC in BC.

Plasma Histone H4 and H4K20 Trimethylation Levels Differ Between Colon Cancer and Precancerous Polyps.

BACKGROUND/AIM: No blood-based biomarkers are available to differentiate between colonic tumors and precancerous polyps. Previously we demonstrated levels of trimethylated H4K20 (H4K20me3) to be lower in blood plasma from patients with colon cancer than those from cancer-free individuals. Herein, we added individuals with precancerous polyps for the first time in order to analyze and investigate the usefulness of plasma H4K20me3 and histone H4 to discriminate colon tumors from precancerous polyps. MATERIALS AND METHODS: The study included a cohort of 185 individuals undergoing colonoscopy. H4K20me3 and histone H4, measured by an enzyme-linked immunosorbent assay-like assay in plasma, were analyzed according to colonoscopy findings. RESULTS: Levels of H4K20me3 were lower in patients with colon cancer than in individuals with normal colonoscopy and those with precancerous polyps (p=0.02 and p=0.01, respectively). In contrast, highest quantities of histone H4 were measured in those with colon cancer compared to other groups (all p<0.01). CONCLUSION: Beside H4K20me3, plasma histone H4 is a useful marker to discriminate colonic tumors from precancerous polyps and other conditions.

Detection of serum protein and circulating mRNA of cMET, HGF EGF and EGFR levels in lung cancer patients to guide individualized therapy.

BACKGROUND: Reseptor tyrosine kinases (cMET and EGFR) are important in lung cancer targeted therapy. We believe if we can use them as markers for clinicians to help decide the diagnosis of lung cancer. This parameter will be important in serum samples of patients with lung cancer diagnosis and treatment. The aim of this study is aimed to evaluate the clinical utility of serum protein and circulating mRNA of cMET and HGF in lung cancer patients. We also analyzed the correlation of mRNA expression with clinicopathologic parameters. METHODS: We performed enzyme-linked immunosorbent assay (ELISA) to measure and compare serum protein and circulating mRNA of cMET and HGF levels in peripheral blood from 60 lung cancer patients and 40 healthy control group. RESULTS: We found that both protein and gene expression levels of serum c-MET, HGF and EGFR were significantly higher in patients with lung cancer than control group. There was no association between HGF, cMET, EGF, EGFR (both protein and gene) expression levels with age, gender, smoking habit, COPD, pathological types or tumor size, stage, metastatic-non metastatic adenocarcinoma-squamous carcinoma, SCLC-NSCLC. As a result of ROC analysis, serum cMET (AUC: 0.892) and HGF protein (AUC: 0.784) were diagnosed in lung cancer patients (Fig. 1). The AUC values of serum EGF and EGFR proteins were calculated to be 0.631 and 0.692, respectively. CONCLUSION: To our knowledge this is the first study comparing the levels of protein and mRNA in the serum material of HGF, c-MET, EGF and EGFR parameters in lung cancer patients' blood samples. Further prospective studies with more participants for better understanding of mechanism and effect for HGF and c-MET inhibitors in lung cancer will help us to identify of these biomarkers role for guiding us to sellect individualized itargeted therapies.

PCA3 Silencing Sensitizes Prostate Cancer Cells to Enzalutamide-mediated Androgen Receptor Blockade.

BACKGROUND/AIM: Prostate cancer (PCa) is an androgen-dependent disease. Novel anti-androgens (i.e. enzalutamide) have recently been developed for the treatment of patients with metastatic castration-resistant prostate cancer (CRPC). Evidence is accumulating that prostate cancer antigen 3 (PCA3) is involved in androgen receptor (AR) signaling. Here, in combination with enzalutamide-mediated AR blockade, we investigated the effect of PCA3 targeting on the viability of PCa cells. MATERIALS AND METHODS: In hormone-sensitive LNCaP cells, AR-overexpressing LNCaP-AR+ cells and VCaP cells (representing CRPC), PCA3 was silenced using siRNA oligonucleotides. Gene expression and cell viability was assessed in PCA3-silenced and/or AR-blocked cells. RESULTS: PCA3 targeting reduced the expression of AR-related genes (i.e. prostate-specific antigen (PSA) and prostate-specific transcript 1 (non-protein coding) (PCGEM1)) and potentiated the effect of enzalutamide. Proliferation of PCa cells was suppressed upon PCA3 silencing with a greater effect in LNCaP-AR+ cells. Furthermore, PCA3 silencing sensitized PCa cells to enzalutamide-induced loss of cell growth. CONCLUSION: PCA3, as a therapeutic target in PCa, might be used to potentiate AR antagonists.

Accumulation of GAS5 in exosomes is a marker of apoptosis induction.

Long non-coding RNAs (lncRNAs) are key regulatory molecules in many fundamental cellular processes and their deregulation is assumed to contribute to carcinogenesis. Exosomal lncRNAs are thought to be involved in the dissemination of cell signals to control local cellular microenvironments. In the current study, exosomal expression of growth arrest specific 5 (GAS5), an inhibitor of cell proliferation and promoter of apoptosis, was evaluated in apoptotic processes initiated by different mechanisms. Therefore, MCF-7 and MDA-MB-231 breast cancer cells were treated with Taxol (2 and 10 nM) and bleomycin (2 and 10 ng/ml) for 24 h. Following cell viability determination and measurement of apoptosis, cellular and exosomal expression levels of GAS5 were investigated using a quantitative polymerase chain reaction assay. The findings indicate that Taxol is more toxic than bleomycin at the indicated doses and the effect was more evident in the MCF-7 cells. Despite varying toxicity rates, comparable levels of apoptotic nucleosomes were measured between Taxol- and bleomycin-treated cells. Upon drug treatment, cellular expression levels of GAS rose (≤1.5-fold) in the two cell lines. It appears that even a small increase in cellular expression leads to exosomal enrichment, as the accumulation of GAS5 in exosomes was marked in the MCF-7 cells (≤5.8-fold). Compared with the MCF-7 cells, the extent of GAS5 enrichment in the exosomes secreted from MDA-MB-231 cells was moderate (≤1.9-fold), potentially as a result of reduced cell death. The present study indicates that GAS5 accumulation in exosomes is a prevalent event in apoptotic processes that are initiated by different mechanisms.

Do circulating long non-coding RNAs (lncRNAs) (LincRNA-p21, GAS 5, HOTAIR) predict the treatment response in patients with head and neck cancer treated with chemoradiotherapy?

Long non-coding RNAs (lncRNAs) have been shown to be aberrantly expressed in head and neck cancer (HNC). The aim of the present study was to evaluate plasma levels of three lncRNA molecules (lincRNA-p21, GAS5, and HOTAIR) in the treatment response in HNC patients treated with radical chemoradiotherapy (CRT). Forty-one patients with HNC were enrolled in the study. Most of the patients had nasopharyngeal carcinoma (n = 27, 65.9 %) and locally advanced disease. Blood was drawn at baseline and treatment evaluation 4.5 months after therapy. lncRNAs in plasma were measured by semiquantitative PCR. Treatment response was evaluated according to clinical examination, RECIST and PERCIST criteria based on magnetic resonance imaging (MRI), and positron emission tomography with computed tomography (PET/CT) findings. Complete response (CR) rates were 73.2, 36.6, and 50 % for clinical investigation, PET/CT-, or MRI-based response evaluation, respectively. Predictive value of lncRNAs was investigated in patients with CR vs. those with partial response (PR)/progressive disease (PD). We found that post-treatment GAS5 levels in patients with PR/PD were significantly higher compared with patients with CR based on clinical investigation (p = 0.01). Receiver operator characteristic (ROC) analysis showed that at a cutoff value of 0.3 of GAS5, sensitivity and specificity for clinical tumor response were 82 and 77 %, respectively. Interestingly, pretreatment GAS5 levels were significantly increased in patients with PR/PD compared to those with CR upon MRI-based response evaluation (p = 0.042). In contrast to GAS5, pretreatment or post-treatment lincRNA-p21 and HOTAIR levels were not informative for treatment response. Our results suggest that circulating GAS5 could be a biomarker in predicting treatment response in HNC patients.

Global quantification of heterochromatin-associated histone methylations in cell lines with differential sensitivity to ionizing radiation.

Histone modifications are involved in the DNA damage response (DDR). Here, by utilizing an ELISA immunoassay we assessed the methylation at H3K9 (H3K9me2 and H3K9me3) in two cell lines with differential sensitivity to radiation-induced apoptosis, HeLa (sensitive) and MCF-7 (resistant). We found that DNA damage induction by γ-irradiation leads to considerable accumulation (up to 5-fold) of H3K9me2 and H3K9me3, but not of H4K20me3 (control modification) in MCF-7 cells (p<0.05). Interestingly, a lower dose (2 Gy) was more effective than 5 Gy. In HeLa cells a smaller effect (approx. 1.5-1.8-fold) was evident only at 5 Gy. In conclusion, our findings reveal that DNA damage leads to specific accumulation of H3K9me2 and H3K9me3 in a cell-type specific manner.

Exosomal lncRNA-p21 levels may help to distinguish prostate cancer from benign disease.

Exosomes are membranous vesicles containing various biomolecules including lncRNAs which are involved in cellular communication and are secreted from many cells including cancer cells. In our study, investigated the exosomal GAS5 and lincRNA-p21 lncRNA levels in urine samples from 30 patients with prostate cancer (PCa) and 49 patients with benign prostatic hyperplasia. Quantification of lncRNA molecules was performed by real-time PCR. We observed a significant difference in the exosomal lincRNA-p21 levels between PCa and BPH patients whereas the GAS5 levels did not reveal a difference. Our data suggest that the discriminative potential of exosomal lincRNA-p21 levels may help to improve the diagnostic prediction of the malignant state for patients with PCa.

Assessment of circulating serum DNA integrity in colorectal cancer patients.

UNLABELLED: Background /Aim: Studies evaluating the integrity of cell-fee DNA (cfDNA) in colorectal cancer (CRC) have led to inconsistent results. Herein, we analyzed the utility of two different DNA integrity indexes (ACTB(384)/ACTB(106) and ALU(247)/ALU(115)) to assess cfDNA fragmentation in Turkish CRC patients. The correlation of circulating nucleosomes (cNUC) with the fragment sizes was also evaluated. MATERIALS AND METHODS: Seventy two CRC patients and 42 CRC-free control individuals were enrolled in the study. cfDNA was analyzed by quantitative polymerase chain reaction (qPCR). RESULTS: While with ALU(247)/ALU(115)there was a small difference between the groups, an approximately 3-fold (median values=0.12 and 0.34) lower integrity was found in the patients using the ACTB(384)/ACTB(106) ratio (p=0.06). The correlation between cNUC and qPCR threshold cycles was much higher for shorter fragments. CONCLUSION: Lower DNA integrity and the predominance of mononuclesomes in serum reveal high fragmentation of cfDNA in CRC patients.

Long non-coding RNAs with low expression levels in cells are enriched in secreted exosomes.

Long non-coding RNAs (lncRNAs) are involved in regulating chromatin modifications, gene transcription, mRNA translation, and protein function. We recently reported a high variation in the basal expression levels of a panel of lncRNAs in HeLa and MCF-7 cells and their differential response to DNA damage induction. Here, we hypothesized that lncRNA molecules with different cellular expression may have a differential abundance in secreted exosomes, and their exosome levels would reflect cellular response to DNA damage. MALAT1, HOTAIR, lincRNA-p21, GAS5, TUG1, CCND1-ncRNA in exosomes secreted from cultured cells were characterized. A different expression pattern of lncRNAs in exosomes was seen compared to cells. RNA molecules with relative low expression levels (lincRNA-p21, HOTAIR, ncRNA-CCND1) were highly enriched in exosomes. TUG1 and GAS5 levels were moderately elevated in exosomes, whereas MALAT1--which was the most abundant molecule in cells--was present at levels comparable to its cellular levels. lincRNA-p21 and ncRNA-CCND1 were the main molecules; exosome levels of them best reflect the change of their cellular levels upon exposure of the cells to bleomycin-induced DNA damage. In conclusion, we provide evidence that lncRNAs have a differential abundance in exosomes, indicating a selective loading.

Investigation of circulating lncRNAs in B-cell neoplasms.

Long non-coding RNAs (lncRNA) which are longer than 200 base pairs in length, play an important role in cellular machinery. Chronic lymphocytic leukemia (CLL) and multiple myeloma (MM) are neoplasms of B-cells. In our study we aimed to investigate circulating lncRNA levels of CLL and MM patients. For this purpose we selected 5 candidate lncRNAs (TUG1, LincRNA-p21, MALAT1, HOTAIR, and GAS5) where the first two are regulated by p53. Analyses were performed by real-time PCR using cDNA synthesized from plasma RNAs. In both disease groups differential levels of plasma lncRNAs were observed. LincRNA-p21 was the only molecule displaying significant changes in the CLL group while all remaining lncRNAs showed significant differences in the MM group. In the MM group only TUG1 showed higher levels than the healthy volunteers. In conclusion, the expression levels of the candidate lncRNA molecules display a general trend for tissue- and disease-specific expression which can provide important potential biomarkers specific to the particular disease type. However, further studies are necessary to elucidate their involvement in disease development and progression.